Abstract: Six segments within the subunit beta-A of the follicular inhibin have been synthesized by an improved solid phase procedure on p-methyl-benzhydrylamine (1% divinylbenzene) resin. The courses of the syntheses were monitored by quantitative ninhydrin assays and amino acid analyses. Following the cleavage by HF-pcresol (9:1 V/V), the peptides were extracted with anhydrous trifluoroacetic acid containing 1% dithiothreitol and precipitated with dry ethyl ether. The purification was achieved uniquely by reverse phase HPLC and final products were craracserized by several TLC systems, analytical HPLC and amino acid analyses. Pituitary cell culture bioassays were performed to ascertain their biological activities. However, among these synthetic peptides, the small peptides Ib-β_a(37～39)NH₂(Ⅰ), Ib-β_A(34～39)NH₂(Ⅱ), and ib-β_A(30～39)NH₂(Ⅲ)showed no significant supression on the LHRH-induced FSH secretion; the large peptides Ib-β_A(23～39)NH₂(Ⅳ), Ib-β_A(16～39)NH₂(Ⅴ), and Ib-β_A(14～39)NH₂(Ⅵ)lack adequate solubility in neutral media, and other methods are to be sought to test their bioactivities.